The morphodynamics of wave on a monsoon-dominated coasts: West coast of GoT

Globally, coastal areas are eroding due to climate change, which influences sea level rise, storm surge, cyclones, and hurricanes. During the past two decades, the coastline areas bordering the Gulf of Thailand have been gradually eroded and extended, with no indication of subsiding, specifically during the northeast monsoon storm season. Subsequently, this research aims to determine how beaches alter along the west coast of Gulf of Thailand during different monsoon seasons. Beach profile surveys were performed throughout the southwest monsoon, the transition monsoon, and the northeast monsoon. The complexity of coastal dynamics, such as wave parameters, was applied to examine the wave features in the five (5) sampling stations along the west coast of Gulf of Thailand during the monsoon seasons to comprehend the issue better. The numerical modelling with MIKE 21 SW illustrates Gulf of Thailand’s West Coast beaches, primarily erosional beaches subject to monsoon wave conditions, especially at Singhanakhon beach, with a great loss of −9.15 m3 of sand volume. Nevertheless, erosion persisted as a concern resulting from interactions of coastal structures with few processes such as wave characteristics and sediment budget. Hence, comprehending coastal features and hydrodynamic processes is essential for bridging the issue’s knowledge gap and offering alternatives in sustainable coastal management.